The present invention relates generally to forming a radio-frequency identification (RFID) tag which includes an antenna and chip or strap based chip on or within fabric or other material. Specifically, the antenna is provided for potential use with a printed fabric labels (PFL) which may be used for example as care labels for garments or apparel items.
Radio-frequency identification (“RFID”) is the use of electromagnetic energy (“EM energy”) to stimulate a responsive device (known as an RFID “tag” or transponder) to identify itself and in some cases, provide additionally stored data. RFID tags typically include a semiconductor device commonly called the “chip” on which are provided a memory and operating circuitry, which then is connected to an antenna. Chips can be mounted directly on an antenna or may be provided with straps in order to facilitate the connection to an antenna. Typically, RFID tags act as transponders, providing information stored in the chip memory in response to a radio frequency (“RF”) interrogation signal received from a reader, also referred to as an interrogator. In the case of passive RFID devices, the energy of the interrogation signal also provides the necessary energy to operate the RFID device. Active RFID tags can have their own power supply such as a battery and does not require the energy of activation as with passive tags.
RFID tags may be incorporated into or attached to articles to be tracked, such as apparel items, garments, accessories, consumer goods, packaging and the like. In some cases, the tag may be attached to the outside of an article with adhesive, tape, sewn in or attached to the item, welded, or other means and in other cases, the tag may be inserted within the article, such as being included in the packaging, located within the container of the article or inserted into a label or tag, such as between plies of a label or tag stock. The RFID tags are manufactured with a unique identification number which is typically a simple serial number of a few bytes with a check digit attached. This identification number is incorporated into the tag during manufacture. The user typically cannot alter this serial/identification number and manufacturers guarantee that each serial number is used only once. This configuration represents the low cost end of the technology in that the RFID tag is read-only and it responds to an interrogation signal only with its identification number. Typically, the tag continuously responds with its identification number. Data transmission to the tag is not possible. These tags are very low cost and are produced in enormous quantities.
Such read-only RFID tags typically are permanently attached to an article to be tracked and, once attached, the serial number of the tag is associated with its host article in a computer data base. Specifically, an object of the tag is to associate it with an article throughout the article's life in a particular facility, such as a manufacturing facility, a transport vehicle, a health care facility, a pharmacy storage area, or other environment, so that the article may be located, identified, and tracked, as it is moved. Tracking the articles through the facility can assist in generating more efficient dispensing and inventory control systems as well as improving work flow in a facility. This results in better inventory control and lowered costs. In the case of medical supplies and devices, it is desirable to develop accurate tracking, inventory control systems, and dispensing systems so that RFID tagged devices and articles may be located quickly should the need arise, and may be identified for other purposes, such as expiration dates or recalls.
Many RFID tags used today are passive in that they do not have a battery or other autonomous power supply and instead, must rely on the interrogating energy provided by an RFID reader to provide power to activate the tag. Passive RFID tags require an electromagnetic field of energy of a certain frequency range and certain minimum intensity in order to achieve activation of the tag and transmission of its stored data. Another choice is an active RFID tag; however, such tags require an accompanying battery to provide power to activate the tag, thus increasing the expense and potentially the size of the tag and making them undesirable for use in a large number of applications where cost is a principal consideration.
Depending on the requirements of the RFID tag application, such as the physical size of the articles to be identified, cost, their location, and the ability to reach them easily, tags may need to be read from a short distance or a long distance by an RFID reader. Furthermore, the read range (i.e., the range of the interrogation and/or response signals) of RFID tags is also limited. The present invention discloses an RFID tag that is formed as part of a printed fabric label (PFL). One benefit in the art to using a RFID tag incorporated into a PFL is that it minimizes the use of PET (polyethylene terephthalate) or other substrates which is desirable for recyclability and sustainability purposes.